Move BinaryCacheStore / LocalBinaryCacheStore from Hydra
So you can now do: $ NIX_REMOTE=file:///tmp/binary-cache nix-store -qR /nix/store/...
This commit is contained in:
parent
b584a0e7de
commit
263187a2ec
292
src/libstore/binary-cache-store.cc
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292
src/libstore/binary-cache-store.cc
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#include "binary-cache-store.hh"
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#include "sync.hh"
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#include "archive.hh"
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#include "compression.hh"
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#include "derivations.hh"
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#include "globals.hh"
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#include "nar-info.hh"
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#include "worker-protocol.hh"
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#include <chrono>
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namespace nix {
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BinaryCacheStore::BinaryCacheStore(std::shared_ptr<Store> localStore,
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const Path & secretKeyFile, const Path & publicKeyFile)
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: localStore(localStore)
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{
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if (secretKeyFile != "")
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secretKey = std::unique_ptr<SecretKey>(new SecretKey(readFile(secretKeyFile)));
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if (publicKeyFile != "") {
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publicKeys = std::unique_ptr<PublicKeys>(new PublicKeys);
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auto key = PublicKey(readFile(publicKeyFile));
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publicKeys->emplace(key.name, key);
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}
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}
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void BinaryCacheStore::init()
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{
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std::string cacheInfoFile = "nix-cache-info";
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if (!fileExists(cacheInfoFile))
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upsertFile(cacheInfoFile, "StoreDir: " + settings.nixStore + "\n");
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}
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const BinaryCacheStore::Stats & BinaryCacheStore::getStats()
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{
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return stats;
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}
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Path BinaryCacheStore::narInfoFileFor(const Path & storePath)
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{
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assertStorePath(storePath);
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return storePathToHash(storePath) + ".narinfo";
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}
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void BinaryCacheStore::addToCache(const ValidPathInfo & info,
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const string & nar)
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{
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auto narInfoFile = narInfoFileFor(info.path);
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if (fileExists(narInfoFile)) return;
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auto narInfo = make_ref<NarInfo>(info);
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narInfo->narSize = nar.size();
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narInfo->narHash = hashString(htSHA256, nar);
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if (info.narHash.type != htUnknown && info.narHash != narInfo->narHash)
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throw Error(format("refusing to copy corrupted path ‘%1%’ to binary cache") % info.path);
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/* Compress the NAR. */
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narInfo->compression = "xz";
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auto now1 = std::chrono::steady_clock::now();
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string narXz = compressXZ(nar);
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auto now2 = std::chrono::steady_clock::now();
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narInfo->fileHash = hashString(htSHA256, narXz);
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narInfo->fileSize = narXz.size();
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auto duration = std::chrono::duration_cast<std::chrono::milliseconds>(now2 - now1).count();
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printMsg(lvlTalkative, format("copying path ‘%1%’ (%2% bytes, compressed %3$.1f%% in %4% ms) to binary cache")
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% narInfo->path % narInfo->narSize
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% ((1.0 - (double) narXz.size() / nar.size()) * 100.0)
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% duration);
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/* Atomically write the NAR file. */
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narInfo->url = "nar/" + printHash32(narInfo->fileHash) + ".nar.xz";
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if (!fileExists(narInfo->url)) {
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stats.narWrite++;
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upsertFile(narInfo->url, narXz);
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} else
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stats.narWriteAverted++;
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stats.narWriteBytes += nar.size();
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stats.narWriteCompressedBytes += narXz.size();
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stats.narWriteCompressionTimeMs += duration;
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/* Atomically write the NAR info file.*/
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if (secretKey) narInfo->sign(*secretKey);
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upsertFile(narInfoFile, narInfo->to_string());
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{
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auto state_(state.lock());
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state_->narInfoCache.upsert(narInfo->path, narInfo);
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stats.narInfoCacheSize = state_->narInfoCache.size();
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}
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stats.narInfoWrite++;
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}
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NarInfo BinaryCacheStore::readNarInfo(const Path & storePath)
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{
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{
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auto state_(state.lock());
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auto res = state_->narInfoCache.get(storePath);
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if (res) {
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stats.narInfoReadAverted++;
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return **res;
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}
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}
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auto narInfoFile = narInfoFileFor(storePath);
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auto narInfo = make_ref<NarInfo>(getFile(narInfoFile), narInfoFile);
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assert(narInfo->path == storePath);
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stats.narInfoRead++;
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if (publicKeys) {
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if (!narInfo->checkSignature(*publicKeys))
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throw Error(format("invalid signature on NAR info file ‘%1%’") % narInfoFile);
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}
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{
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auto state_(state.lock());
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state_->narInfoCache.upsert(storePath, narInfo);
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stats.narInfoCacheSize = state_->narInfoCache.size();
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}
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return *narInfo;
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}
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bool BinaryCacheStore::isValidPath(const Path & storePath)
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{
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return fileExists(narInfoFileFor(storePath));
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}
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void BinaryCacheStore::exportPath(const Path & storePath, bool sign, Sink & sink)
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{
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assert(!sign);
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auto res = readNarInfo(storePath);
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auto nar = getFile(res.url);
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stats.narRead++;
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stats.narReadCompressedBytes += nar.size();
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/* Decompress the NAR. FIXME: would be nice to have the remote
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side do this. */
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if (res.compression == "none")
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;
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else if (res.compression == "xz")
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nar = decompressXZ(nar);
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else
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throw Error(format("unknown NAR compression type ‘%1%’") % nar);
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stats.narReadBytes += nar.size();
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printMsg(lvlTalkative, format("exporting path ‘%1%’ (%2% bytes)") % storePath % nar.size());
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assert(nar.size() % 8 == 0);
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sink((unsigned char *) nar.c_str(), nar.size());
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// FIXME: check integrity of NAR.
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sink << exportMagic << storePath << res.references << res.deriver << 0;
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}
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Paths BinaryCacheStore::importPaths(bool requireSignature, Source & source)
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{
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assert(!requireSignature);
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Paths res;
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while (true) {
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unsigned long long n = readLongLong(source);
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if (n == 0) break;
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if (n != 1) throw Error("input doesn't look like something created by ‘nix-store --export’");
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res.push_back(importPath(source));
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}
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return res;
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}
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struct TeeSource : Source
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{
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Source & readSource;
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std::string data;
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TeeSource(Source & readSource) : readSource(readSource)
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{
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}
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size_t read(unsigned char * data, size_t len)
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{
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size_t n = readSource.read(data, len);
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this->data.append((char *) data, n);
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return n;
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}
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};
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struct NopSink : ParseSink
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{
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};
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Path BinaryCacheStore::importPath(Source & source)
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{
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/* FIXME: some cut&paste of LocalStore::importPath(). */
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/* Extract the NAR from the source. */
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TeeSource tee(source);
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NopSink sink;
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parseDump(sink, tee);
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uint32_t magic = readInt(source);
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if (magic != exportMagic)
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throw Error("Nix archive cannot be imported; wrong format");
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ValidPathInfo info;
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info.path = readStorePath(source);
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info.references = readStorePaths<PathSet>(source);
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readString(source); // deriver, don't care
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bool haveSignature = readInt(source) == 1;
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assert(!haveSignature);
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addToCache(info, tee.data);
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return info.path;
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}
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ValidPathInfo BinaryCacheStore::queryPathInfo(const Path & storePath)
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{
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return ValidPathInfo(readNarInfo(storePath));
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}
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void BinaryCacheStore::querySubstitutablePathInfos(const PathSet & paths,
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SubstitutablePathInfos & infos)
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{
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PathSet left;
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if (!localStore) return;
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for (auto & storePath : paths) {
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if (!localStore->isValidPath(storePath)) {
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left.insert(storePath);
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continue;
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}
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ValidPathInfo info = localStore->queryPathInfo(storePath);
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SubstitutablePathInfo sub;
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sub.references = info.references;
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sub.downloadSize = 0;
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sub.narSize = info.narSize;
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infos.emplace(storePath, sub);
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}
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if (settings.useSubstitutes)
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localStore->querySubstitutablePathInfos(left, infos);
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}
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void BinaryCacheStore::buildPaths(const PathSet & paths, BuildMode buildMode)
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{
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for (auto & storePath : paths) {
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assert(!isDerivation(storePath));
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if (isValidPath(storePath)) continue;
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if (!localStore)
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throw Error(format("don't know how to realise path ‘%1%’ in a binary cache") % storePath);
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localStore->addTempRoot(storePath);
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if (!localStore->isValidPath(storePath))
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localStore->ensurePath(storePath);
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ValidPathInfo info = localStore->queryPathInfo(storePath);
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for (auto & ref : info.references)
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if (ref != storePath)
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ensurePath(ref);
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StringSink sink;
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dumpPath(storePath, sink);
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addToCache(info, sink.s);
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}
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}
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void BinaryCacheStore::ensurePath(const Path & path)
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{
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buildPaths({path});
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}
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}
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170
src/libstore/binary-cache-store.hh
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170
src/libstore/binary-cache-store.hh
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#pragma once
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#include "crypto.hh"
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#include "store-api.hh"
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#include "lru-cache.hh"
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#include "sync.hh"
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#include "pool.hh"
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#include <atomic>
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namespace nix {
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struct NarInfo;
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class BinaryCacheStore : public Store
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{
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private:
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std::unique_ptr<SecretKey> secretKey;
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std::unique_ptr<PublicKeys> publicKeys;
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std::shared_ptr<Store> localStore;
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struct State
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{
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LRUCache<Path, ref<NarInfo>> narInfoCache{32 * 1024};
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};
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Sync<State> state;
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protected:
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BinaryCacheStore(std::shared_ptr<Store> localStore,
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const Path & secretKeyFile, const Path & publicKeyFile);
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virtual bool fileExists(const std::string & path) = 0;
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virtual void upsertFile(const std::string & path, const std::string & data) = 0;
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virtual std::string getFile(const std::string & path) = 0;
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public:
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virtual void init();
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struct Stats
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{
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std::atomic<uint64_t> narInfoRead{0};
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std::atomic<uint64_t> narInfoReadAverted{0};
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std::atomic<uint64_t> narInfoWrite{0};
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std::atomic<uint64_t> narInfoCacheSize{0};
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std::atomic<uint64_t> narRead{0};
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std::atomic<uint64_t> narReadBytes{0};
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std::atomic<uint64_t> narReadCompressedBytes{0};
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std::atomic<uint64_t> narWrite{0};
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std::atomic<uint64_t> narWriteAverted{0};
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std::atomic<uint64_t> narWriteBytes{0};
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std::atomic<uint64_t> narWriteCompressedBytes{0};
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std::atomic<uint64_t> narWriteCompressionTimeMs{0};
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};
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const Stats & getStats();
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private:
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Stats stats;
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std::string narInfoFileFor(const Path & storePath);
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void addToCache(const ValidPathInfo & info, const string & nar);
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protected:
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NarInfo readNarInfo(const Path & storePath);
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public:
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bool isValidPath(const Path & path) override;
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PathSet queryValidPaths(const PathSet & paths) override
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{ abort(); }
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PathSet queryAllValidPaths() override
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{ abort(); }
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ValidPathInfo queryPathInfo(const Path & path) override;
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Hash queryPathHash(const Path & path) override
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{ abort(); }
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void queryReferrers(const Path & path,
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PathSet & referrers) override
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{ abort(); }
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Path queryDeriver(const Path & path) override
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{ abort(); }
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PathSet queryValidDerivers(const Path & path) override
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{ abort(); }
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PathSet queryDerivationOutputs(const Path & path) override
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{ abort(); }
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StringSet queryDerivationOutputNames(const Path & path) override
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{ abort(); }
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Path queryPathFromHashPart(const string & hashPart) override
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{ abort(); }
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PathSet querySubstitutablePaths(const PathSet & paths) override
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{ abort(); }
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void querySubstitutablePathInfos(const PathSet & paths,
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SubstitutablePathInfos & infos) override;
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Path addToStore(const string & name, const Path & srcPath,
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bool recursive = true, HashType hashAlgo = htSHA256,
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PathFilter & filter = defaultPathFilter, bool repair = false) override
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{ abort(); }
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Path addTextToStore(const string & name, const string & s,
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const PathSet & references, bool repair = false) override
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{ abort(); }
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void exportPath(const Path & path, bool sign,
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Sink & sink) override;
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Paths importPaths(bool requireSignature, Source & source) override;
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Path importPath(Source & source);
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void buildPaths(const PathSet & paths, BuildMode buildMode = bmNormal) override;
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BuildResult buildDerivation(const Path & drvPath, const BasicDerivation & drv,
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BuildMode buildMode = bmNormal) override
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{ abort(); }
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void ensurePath(const Path & path) override;
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void addTempRoot(const Path & path) override
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{ abort(); }
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void addIndirectRoot(const Path & path) override
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{ abort(); }
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void syncWithGC() override
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{ }
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Roots findRoots() override
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{ abort(); }
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void collectGarbage(const GCOptions & options, GCResults & results) override
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{ abort(); }
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PathSet queryFailedPaths() override
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{ return PathSet(); }
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void clearFailedPaths(const PathSet & paths) override
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{ }
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void optimiseStore() override
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{ }
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bool verifyStore(bool checkContents, bool repair) override
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{ return true; }
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};
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}
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44
src/libstore/local-binary-cache-store.cc
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44
src/libstore/local-binary-cache-store.cc
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#include "local-binary-cache-store.hh"
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namespace nix {
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LocalBinaryCacheStore::LocalBinaryCacheStore(std::shared_ptr<Store> localStore,
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const Path & secretKeyFile, const Path & publicKeyFile,
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const Path & binaryCacheDir)
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: BinaryCacheStore(localStore, secretKeyFile, publicKeyFile)
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, binaryCacheDir(binaryCacheDir)
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{
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}
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void LocalBinaryCacheStore::init()
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{
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createDirs(binaryCacheDir + "/nar");
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BinaryCacheStore::init();
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}
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static void atomicWrite(const Path & path, const std::string & s)
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{
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Path tmp = path + ".tmp." + std::to_string(getpid());
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AutoDelete del(tmp, false);
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writeFile(tmp, s);
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if (rename(tmp.c_str(), path.c_str()))
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throw SysError(format("renaming ‘%1%’ to ‘%2%’") % tmp % path);
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del.cancel();
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}
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bool LocalBinaryCacheStore::fileExists(const std::string & path)
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{
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return pathExists(binaryCacheDir + "/" + path);
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}
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void LocalBinaryCacheStore::upsertFile(const std::string & path, const std::string & data)
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{
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atomicWrite(binaryCacheDir + "/" + path, data);
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}
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std::string LocalBinaryCacheStore::getFile(const std::string & path)
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{
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return readFile(binaryCacheDir + "/" + path);
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}
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}
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31
src/libstore/local-binary-cache-store.hh
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31
src/libstore/local-binary-cache-store.hh
Normal file
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#pragma once
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#include "binary-cache-store.hh"
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namespace nix {
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class LocalBinaryCacheStore : public BinaryCacheStore
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{
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private:
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Path binaryCacheDir;
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public:
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LocalBinaryCacheStore(std::shared_ptr<Store> localStore,
|
||||
const Path & secretKeyFile, const Path & publicKeyFile,
|
||||
const Path & binaryCacheDir);
|
||||
|
||||
void init() override;
|
||||
|
||||
protected:
|
||||
|
||||
bool fileExists(const std::string & path) override;
|
||||
|
||||
void upsertFile(const std::string & path, const std::string & data) override;
|
||||
|
||||
std::string getFile(const std::string & path) override;
|
||||
|
||||
};
|
||||
|
||||
}
|
|
@ -313,18 +313,24 @@ void Store::exportPaths(const Paths & paths,
|
|||
|
||||
|
||||
#include "local-store.hh"
|
||||
#include "serialise.hh"
|
||||
#include "remote-store.hh"
|
||||
#include "local-binary-cache-store.hh"
|
||||
|
||||
|
||||
namespace nix {
|
||||
|
||||
|
||||
ref<Store> openStore(bool reserveSpace)
|
||||
ref<Store> openStoreAt(const std::string & uri, bool reserveSpace)
|
||||
{
|
||||
if (std::string(uri, 0, 7) == "file://") {
|
||||
return make_ref<LocalBinaryCacheStore>(std::shared_ptr<Store>(0),
|
||||
"", "", // FIXME: allow the signing key to be set
|
||||
std::string(uri, 7));
|
||||
}
|
||||
|
||||
enum { mDaemon, mLocal, mAuto } mode;
|
||||
|
||||
mode = getEnv("NIX_REMOTE") == "daemon" ? mDaemon : mAuto;
|
||||
mode = uri == "daemon" ? mDaemon : mAuto;
|
||||
|
||||
if (mode == mAuto) {
|
||||
if (LocalStore::haveWriteAccess())
|
||||
|
@ -341,4 +347,10 @@ ref<Store> openStore(bool reserveSpace)
|
|||
}
|
||||
|
||||
|
||||
ref<Store> openStore(bool reserveSpace)
|
||||
{
|
||||
return openStoreAt(getEnv("NIX_REMOTE"), reserveSpace);
|
||||
}
|
||||
|
||||
|
||||
}
|
||||
|
|
|
@ -419,8 +419,28 @@ Path computeStorePathForText(const string & name, const string & s,
|
|||
void removeTempRoots();
|
||||
|
||||
|
||||
/* Factory method: open the Nix database, either through the local or
|
||||
remote implementation. */
|
||||
/* Return a Store object to access the Nix store denoted by
|
||||
‘uri’ (slight misnomer...). Supported values are:
|
||||
|
||||
* ‘direct’: The Nix store in /nix/store and database in
|
||||
/nix/var/nix/db, accessed directly.
|
||||
|
||||
* ‘daemon’: The Nix store accessed via a Unix domain socket
|
||||
connection to nix-daemon.
|
||||
|
||||
* ‘file://<path>’: A binary cache stored in <path>.
|
||||
|
||||
If ‘uri’ is empty, it defaults to ‘direct’ or ‘daemon’ depending on
|
||||
whether the user has write access to the local Nix store/database.
|
||||
|
||||
The Boolean ‘reserveSpace’ denotes whether some disk space should
|
||||
be reserved to enable future garbage collector runs. It should be
|
||||
set to true *unless* you're going to collect garbage.
|
||||
*/
|
||||
ref<Store> openStoreAt(const std::string & uri, bool reserveSpace = true);
|
||||
|
||||
|
||||
/* Open the store indicated by the ‘NIX_REMOTE’ environment variable. */
|
||||
ref<Store> openStore(bool reserveSpace = true);
|
||||
|
||||
|
||||
|
|
84
src/libutil/lru-cache.hh
Normal file
84
src/libutil/lru-cache.hh
Normal file
|
@ -0,0 +1,84 @@
|
|||
#pragma once
|
||||
|
||||
#include <map>
|
||||
#include <list>
|
||||
|
||||
namespace nix {
|
||||
|
||||
/* A simple least-recently used cache. Not thread-safe. */
|
||||
template<typename Key, typename Value>
|
||||
class LRUCache
|
||||
{
|
||||
private:
|
||||
|
||||
size_t maxSize;
|
||||
|
||||
// Stupid wrapper to get around circular dependency between Data
|
||||
// and LRU.
|
||||
struct LRUIterator;
|
||||
|
||||
using Data = std::map<Key, std::pair<LRUIterator, Value>>;
|
||||
using LRU = std::list<typename Data::iterator>;
|
||||
|
||||
struct LRUIterator { typename LRU::iterator it; };
|
||||
|
||||
Data data;
|
||||
LRU lru;
|
||||
|
||||
public:
|
||||
|
||||
LRUCache(size_t maxSize) : maxSize(maxSize) { }
|
||||
|
||||
/* Insert or upsert an item in the cache. */
|
||||
void upsert(const Key & key, const Value & value)
|
||||
{
|
||||
erase(key);
|
||||
|
||||
if (data.size() >= maxSize) {
|
||||
/* Retire the oldest item. */
|
||||
auto oldest = lru.begin();
|
||||
data.erase(*oldest);
|
||||
lru.erase(oldest);
|
||||
}
|
||||
|
||||
auto res = data.emplace(key, std::make_pair(LRUIterator(), value));
|
||||
assert(res.second);
|
||||
auto & i(res.first);
|
||||
|
||||
auto j = lru.insert(lru.end(), i);
|
||||
|
||||
i->second.first.it = j;
|
||||
}
|
||||
|
||||
bool erase(const Key & key)
|
||||
{
|
||||
auto i = data.find(key);
|
||||
if (i == data.end()) return false;
|
||||
lru.erase(i->second.first.it);
|
||||
data.erase(i);
|
||||
return true;
|
||||
}
|
||||
|
||||
/* Look up an item in the cache. If it's exists, it becomes the
|
||||
most recently used item. */
|
||||
// FIXME: use boost::optional?
|
||||
Value * get(const Key & key)
|
||||
{
|
||||
auto i = data.find(key);
|
||||
if (i == data.end()) return 0;
|
||||
|
||||
/* Move this item to the back of the LRU list. */
|
||||
lru.erase(i->second.first.it);
|
||||
auto j = lru.insert(lru.end(), i);
|
||||
i->second.first.it = j;
|
||||
|
||||
return &i->second.second;
|
||||
}
|
||||
|
||||
size_t size()
|
||||
{
|
||||
return data.size();
|
||||
}
|
||||
};
|
||||
|
||||
}
|
Loading…
Reference in a new issue